Seismicity in the Basin and Range Province of Sonora, México, between 2003 and 2011, near the Rupture of the 3 May 1887 Mw 7.5 Earthquake

AbstractThe regional seismicity in the Basin and Range Province of Sonora, México, near the epicentral region of the 3 May 1887 Mw 7.5 earthquake was studied. Body wave arrival times recorded by the local network RESNES (Red Sísmica del Noreste de Sonora) and two regional broadband stations of the RESBAN (Red Sismológica de Banda Ancha del Golfo de California) network were used to locate the seismic sources originating between 2008 and 2011. Preliminary hypocenter coordinates were first determined with the program Hypoinverse (Klein, 2002) and then relocated the initial coordinates with the source-specific station term method (Lin and Shearer, 2005). The same procedure was used in a previous study (Castro et al., 2010) to locate the earthquakes originating in the same region between 2003 and 2007. I also present in this paper a depurated catalog of events recorded from 2003 to 2011. Most relocated events cluster near the faults that ruptured during the 1887 earthquake. Additionally, I document seismicity along Basin and Range Province normal faults south of the 1887 rupture, such as the Villa Hidalgo and Granados faults and the faults bounding the Bacadéhuachi basin. The region of the largest population center, Hermosillo, appears to be seismically quiescent. This observation is supported by a lack of entries in the catalog of the International Seismological Centre (ISC) or documented historical seismicity in that area